Issue #3304365: Do not check excluded folders for symlinks

package_manager/src/Stage.php

@@ -454,7 +454,9 @@ class Stage implements LoggerAwareInterface {
     $this->failureMarker->write($this, $this->getFailureMarkerMessage());
     // Exclude the failure file from the commit operation.
     $ignored_paths = new PathList($event->getExcludedPaths());
-    $ignored_paths->add($this->failureMarker->getPath());
+    $ignored_paths->add([
+      $this->failureMarker->getPath(),
+    ]);
 
     try {
       $this->committer->commit($stage_dir, $active_dir, $ignored_paths, NULL, $timeout);